Graphene is pure carbon in the form of a very thin, nearly transparent sheet, one atom thick. It is remarkably strong for its very low weight (100 times stronger than steel) and it conducts heat and electricity with great efficiency. Graphene is a zero-gap semiconductor. The ability to control the majority carrier type while introducing a bandgap makes hydrogenated graphene a promising method for nanocircuit design (e.g. p-n junctions) in a graphene-based system. Tunability of the carrier type via surface doping removes the requirement for multiple gate electrodes for independent carrier type control, avoiding the need for high quality dielectrics that are difficult to achieve on graphene and are susceptible to leakage currents.
This disclosure provides a method for introducing a bandgap in single layer graphite (graphene) on a SiO2 substrate, while also allowing for independent control of the majority carrier type via surface adsorbates. Specific applications of the invention include patterning graphene samples for nanocircuit design and device integration at various scales, for example, p-n junctions. The technique is reversible, such that the dopant atoms introduced into the graphene can be removed while preserving the original graphene band structure.